This invention relates to a deformable mirror light valve, and particularly to such a light valve having a plurality of transparent electrodes on one surface of a transparent substrate.
Deformable mirror light valves are well-known devices capable of amplifying the light intensity of an optically projected image, e.g., see U.S. Pat. No. 2,896,507 entitled "Arrangement for Amplifying the Light Intensity of an Optically Projected Image," issued on July 28, 1959. Further information on these devices can be found in U.S. Pat. No. 3,716,359 entitled "Cyclic Recording System by the Use of an Elastomer in an Electric Field," issued Feb. 13, 1973, and in U.S. Pat. No. 3,842,406, also entitled "Cyclic Recording System by the Use of an Electric Field," issued Oct. 15, 1974. Generally, the devices are layered structures including a transparent conductor layer, a photoconductor layer, an elastomer layer, a thin flexible layer of conductive metal, and means for applying a voltage across the transparent conductor layer and the flexible layer of conductive metal.
A light image absorbed by the photoconductor layer generates electron hole pairs. The voltage applied across the transparent conductor layer and the thin flexible metal layer causes the mobile carriers to drift in the photoconductor layer. As the oppositely charged carriers separate, a non-uniform charge pattern is formed, thereby causing the thin flexible metal layer to deform.
Although deformable mirror light valves have been developed and are successful for many applications, e.g., projected image displays, widespread use has heretofore been discouraged. For example, it would be desirable to employ such a light valve in combination with an optical scanner wherein the optical information is written into the valve in a scanning mode. Such an approach could take advantage of recent advances in laser scanning techniques. Of particular significance would be the development of a light valve capable of producing a real time, e.g., television rate (with or without storage), projected image display. However, it has been found that conventional light valves create projected images which suffer from nonuniformity in intensity when operated in a scanning mode. Thus, it would be desirable to develop a deformable mirror light valve which exhibits improved image uniformity when operated in a scanning mode.